Polyether-Based Block Co(ter)polymers as Multifunctional Lubricant Additives

A series of polyether-based diblock copolymers were synthesized by sequential organocatalytic ring-opening polymerization (ROP) either hexene oxide (HO) or octene (OO) as the first monomer with propylene (PO) second monomer. In addition, one triblock terpolymer OO, PO, and styrene (SO) was following same method. The ROP catalyzed triethyl borane (TEB)/(phosphazene base t-BuP2) eicosanol initiator. resulting co(ter)polymers have a low polydispersity index good solubility in hydrocarbon-based oils are metal-free. By blending polyoctene (POO) polyhexene (PHO) homopolymers Group II oil (AramcoPrima 230) (2.5 to 5.0 wt %), viscosity (VI) increased from 100 160, thermal stability enhanced up 50 °C. using copolymers, POO-block-poly(propylene oxide) (POO-b-PPO) PHO-block-PPO (PHO-b-PPO), instead homopolymers, VI almost same, but exhibits superior lubrication performance, friction wear decreasing 46 86%, respectively. addition PSO block POO-b-PPO chain (POO-b-PPO-b-PSO) further improves worsens rheological tribological properties (i.e., VI, friction, wear) lubricating oils.